1. Field of the Invention
The present invention relates generally to oral syringe packaging equipment and more specifically to a partially automated system for preparing patient-specific doses of selected pharmaceutical liquid medication for administration by oral syringe on a just-in-time basis, for use in a hospital pharmacy.
2. Description of the Background
Oral syringes are well known instruments in the medical fields and are used to administer liquid medicine into the mouth, as an alternative to pills which can present a choking hazard or be expectorated, typically for infants/children and uncooperative or geriatric adults. The oral syringe directs liquid medicine to the back of the throat prompting a swallowing response. Injectable syringes, on the other hand, are used to administer medication into the body by injecting its contents through the skin. Injectable syringes utilize a needle on the tip of the syringe. Injectable syringes must be manufactured and packaged in a sterile environment. Research has shown that the potential for adverse drug events within the pediatric inpatient population is about three times as high as among hospitalized adults. See, Joint Commission, Preventing Pediatric Medication Errors, Issue 39 (2008). According to the Commission Report, the most common types of harmful pediatric medication errors were improper dose/quantity (37.5 percent) and unauthorized/wrong drug (13.7 percent), followed by improper preparation or dosage form. Oral syringes help to minimize these problems and are considered the gold standard for delivering medicine to children.
Oral syringes, which are relatively inexpensive and disposable, are comprised of a simple piston pump with a plunger that fits tightly in one end of a cylindrical tube (the barrel) and can be pushed or pulled along inside the barrel to create negative or positive relative pressure within the barrel that causes the syringe to take in or expel a liquid or gas through an orifice (nozzle) at the opposing end of the barrel. An annular flange partially or fully encircling the outside surface of the barrel is typically provided to facilitate compression of the plunger into the barrel. The barrel of an oral syringe is typically made of plastic and is at least partially transparent along its length with graduated markings to indicate the volume of fluid in the syringe based on the position of the plunger, which is thus visible within the barrel. Oral syringes are commonly marked in units of milliliters and come in standard sizes ranging from 0.5 to 60 milliliters. The plunger is also typically plastic as this provides a good seal within the barrel and is inexpensive to produce so as to be disposable, reducing the risk of contamination or transmission of communicable disease. Oral syringes come in a wide range of sizes and with some variation in configuration. For example, some oral syringes have the nozzle located along the central axis while others have the nozzle offset from the central axis. This variability makes it difficult to automate the filling process for oral syringes.
Pharmacies at in-patient medical facilities and other medical institutions fill a large number of prescriptions on a daily basis including prescriptions for liquid or compounded suspension medicines to be administered by oral syringe, and must do so accurately for medical safety reasons. The volume of an oral pediatric prescription's dose is determined by the child's weight. This makes it impractical to stock pre-filled syringes due to the wide range of fill volumes required. As a result, pediatric oral liquid doses are prepared in the hospital pharmacy on a patient-specific, just-in-time basis. The process of filling numerous, variously sized single dose prescriptions for delivery by oral syringe is time consuming, labor intensive and prone to human error. To ensure that the medication is packaged error-free, the pharmacy technician must make sure that: (1) the syringe contains the correct medication; (2) the syringe contains the correct amount of medication; (3) the syringe is capped correctly; (4) the medication has not expired; (5) the medication has not been recalled; (6) the medication, when required, is shaken; (7) the medication, when required, has been properly refrigerated; (8) the medication, when required, has been properly protected from exposure to light; (9) the information on the syringe label is correct; (10) the syringe is placed into the correct bag; (11) the information on the bag containing the syringe is correct; (12) the bag is properly sealed; and (13) the syringe is protected from cross contamination from other medications. The process typically requires a pharmacist or pharmacy technician to retrieve the correct medication from a storage cabinet (with or without light protection) or refrigerated storage area. The liquid medications are typically stored in a container sealed with a safety cap or seal. After confirming the contents of the retrieved container and shaking the medication (if necessary), the technician manually opens the cap and inserts the tip of an oral syringe into the container which has previously been adapted to accept the syringe, inverts the container, and then withdraws the plunger to draw the medication into the barrel of the syringe. After filling with a proper amount, the syringe and medication container are rotated back to the original position, the syringe is removed from the container, the tip of the syringe is covered with a cap for transport to the patient and the syringe is labeled to indicate its content and the intended recipient, and then bagged. Prior to administering the dose, the nurse can determine the amount of the dose by observing where the tip of the plunger or piston is located in the barrel.
Currently, the degree of automation in the hospital pharmacy for the packaging of oral syringes is very limited. Islands of automation exist, such as automatic labeling of the syringe and bagging of the filled and capped syringe to indicate to the administering nurse the content of the syringe. However, the filling and capping of oral syringes are done manually. Scanners, cameras, bar code readers and track-and-trace technology have not been applied on an integrated, comprehensive basis for the packaging of oral syringes in the hospital pharmacy. The potential to reduce medication errors using this technology is thus significant. Automated systems have been developed by Baxa, Inc., For Health Technologies, Inc., Intelligent Hospital Systems and others for the automated filling of injectable syringes.
For example, U.S. Pat. Nos. 6,991,002; 7,017,622; 7,631,475 and 6,976,349 are all drawn to the automated removal of a tip cap from an empty syringe, the placement of the tip cap at a remote location, and the replacement of the tip cap on a filled syringe. U.S. Pat. Nos. 7,117,902 and 7,240,699 are drawn to automated transfer of a drug vial from storage to a fill station. U.S. Pat. No. 5,884,457 shows a method and apparatus for filling syringes using a pump connected by a hose to a fluid source. U.S. Pat. No. 7,610,115 and Application Publication 2010/0017031 show an Automated Pharmacy Admixture System (APAS). U.S. Application Publication 2009/0067973 shows a gripper device for handling syringes of different diameters with tapered or angled gripper fingers. U.S. Pat. No. 7,343,943 shows a medication dose under-fill detection system. U.S. Pat. No. 7,260,447 shows an automated system for fulfilling pharmaceutical prescriptions. U.S. Pat. No. 7,681,606 shows an automated system and process for filling syringes of multiple sizes. U.S. Pat. No. 6,877,530 shows an automated means for withdrawing a syringe plunger. U.S. Pat. No. 5,692,640 shows a system for establishing and maintaining the identity of medication in a vial using preprinted, pressure sensitive, syringe labels.
The foregoing reference machines for packaging injectable syringes. The packaging process required for injectable syringes is significantly different than that for oral syringes. Injectable syringes must be packaged in a sterile environment, as the medication is injected into the body. This requirement adds cost and complexity to the machine. Injectable medications, when packaged on a just-in-time basis as with the Baxa, For Health Technologies, and Intelligent Hospital System machines, must typically be prepared by the machine before the medication is filled into the syringe. The medication preparation process involves diluting the medication or reconstituting the medication from a powdered state with water. This process adds expense and slows down the packaging process as well. The Intelligent Hospital Systems syringe packaging system is designed to be used to package cytotoxic medications which are hazardous. To avoid harm to the operator, this machine uses a robot located within an isolating barrier at considerable cost. The Baxa, For Health Technologies, and Intelligent Hospital System machines require the use of expensive disposable product contact parts when a different medication is to be filled. The foregoing machines are not suitable for packaging oral syringes due to their capital cost, complexity, slow production rates, inability to handle oral medication containers, the requirement of expensive disposable contact parts, and other features that add unnecessary cost and complexity to the process for filling and packaging oral syringes. Consequently, existing automation does not address the needs of medical institutions desiring an affordable pharmacy automation system for patient safety, prescription tracking and improved productivity in the filling and packaging of oral syringes. The present invention was developed to fill this void.
Oral syringes are manufactured in a variety of sizes with differing tip and plunger configurations, as described in part above. Moreover, oral medications are commonly provided and/or stored in bulk form in variously sized, manufacturer-supplied (OEM) bottles or containers having threaded screw caps that must be removed and replaced between uses. Under the prior art, in order to fill an oral syringe from the manufacturer-supplied container, the original container cap must be replaced with a cap that allows insertion of an oral syringe nozzle. Baxa™ sells an “Adapta-Cap”™ bottle adapter in a variety of sizes that replaces the OEM caps to convert a standard prescription or manufacturer bottle into a filling device for oral syringes. These Adapta-Cap™ bottle adapters are screw-on caps with open center-holes capable of accepting an oral syringe nozzle, and a tethered closure. This enables an oral syringe to enter its center hole and withdraw an amount of liquid from the medication container while the medication container is positioned upside down. Unfortunately, the Adapta-Cap™ bottle adapters have no internal valves and are not self-sealing. Thus, for the syringe to be removed from the medication container, both syringe and medication bottle must be up-righted. Once up-righted, the syringe can be removed from the up-righted medication bottle with no leakage. If the medication bottle requires shaking at any given time, it must be done manually or in a separate shaker while upright when using the prior art Adapta-Cap™.
It is known that an adapter cap can include a self-sealing valve for this purpose. For example, U.S. Pat. No. 8,459,312 to Manera et al. (Comar) issued Jun. 11, 2013 shows an adapter to be pressed into the neck of a bottle to receive a syringe for accessing the bottle contents by a syringe. The adapter has a normally closed valve located at that distal end to prevent the contents from leaking out of the bottle if the bottle is inverted. A very similar construct was shown in United States Patent Application 20110130740 by Levy (Baxa) published Jun. 2, 2011 (now abandoned). U.S. Pat. No. 4,493,348 shows a method and apparatus in which oral syringes can be filled using a screw-on adapter cap 12 for connecting the bulk medicine container 10 and a syringe 14 so that the liquid medication can be transferred from the bulk container 10 into the syringe barrel 20. The syringe is inserted into a nozzle 88 of the adapter cap 12 and displaces a detent valve 92 (see U.S. Pat. No. 4,493,348 FIG. 6) that allows medicine to flow through the nozzle 88 into the syringe. When not in use the nozzle 88 may be closed off by a plug 50 attached to a tether 48. The adapter cap 12 is well-suited for manual filling of oral syringes but is not suitable for automated filling.
Additionally, all of the foregoing adapters allow a tapered tip oral syringe to enter a center hole and withdraw an amount of liquid from the medication container while the medication container is positioned upside down, allow an oral syringe be removed from the container while the container is inverted, without leaking, and allow the medication container to be shaken while it is positioned upside down without leaking. However, none can accommodate an oral syringe with a Luer-lock tip. The Luer-lock tip syringe, includes a circular hub about the oral syringe nozzle that screws into in a threaded sleeve on the medicine container cap (see FIG. 39). As a result of a worldwide International Standards Organization directive ISO-80369, certain syringe types will be required to employ Luer-lock fittings to reduce the risk of misconnections between tubes, IV's, enteral devices, etc. In order to accommodate this change, any syringe fill automation system or semi-automatic system suitable for use in a hospital setting should be able to interface syringes with a Luer-lock fitting to a medicine container equipped with an adapter cap that preferably allows insertion, filling and withdrawal in any orientation without leaking, and which preferably enables the medication container to be shaken without leaking. Thus, preferably, a system of filling oral syringes should interface both Luer-lock and tapered tip oral syringes with medicine containers equipped with the appropriate adapter cap. A self-sealing adapter cap may accomplish these goals.
Given the diversity of oral syringes and medicine containers available (and in use), any semi-automated (or fully-automated) system will need sufficient dexterity to manipulate all the myriad prescription bottles containing the pharmaceuticals to be dispensed as well as variously sized oral syringes with tapered and Luer-lock tips, bringing them together in a controlled environment to quickly and accurately fill and label each syringe and to verify its work as it proceeds in order to avoid errors in the process. Such a system would need to be reliably constructed so as to minimize downtime, quickly take and fill orders, be easy to clean and capable of maintaining an environment free from cross contamination. Such a system would also need to be able to interact with a human operator at multiple points in the operation.
Additionally, in-patient medical facilities such as hospitals are moving toward electronic prescription (“e-prescription”) systems which use computer systems to create, modify, review, and/or transmit medication prescriptions from the healthcare provider to the pharmacy. While e-prescribing improves patient safety and saves money by eliminating the inefficiencies and inaccuracies of the manual, handwritten prescription process, any syringe fill automation system suitable for use in a hospital setting must interface with an existing e-prescription system (which records and transmits prescriptions to the pharmacy), and must be capable of filling prescription orders in a just-in-time environment.